To help orthopaedically challenged persons overcome problems in moving from one place to another and to ease the way they move, Amrita University has come up with a self-driving wheelchair.
A team of Assistant Professor, Electronics and Communications Engineering Department, Rajesh Kannan Megalingam, and alumni Raviteja Chinta, Sarath Sreekanth and Akhil Raj developed the self-driving wheelchair under a project of the University's Humanitarian Technology Lab.
The wheelchair moves on fully automated, fixed automatic and manual modes, says Mr. Megalingam. The fully automated mode allows the user to move anywhere in a mapped area. The fixed automatic mode takes the user from his or her current position to a specific point in a mapped area. And, manual modes gives the user the freedom to move around anywhere using a navigation system at his control.
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In the first two modes, though, the user will have to have his area of movement – house or office – completely mapped and fed into the software that runs the wheelchair and at present this cannot be done by the user, but by the person who services or installs the self-driving wheelchair.
The next step is to make the mapping and uploading the map exercise user-friendly, the assistant professor says.
The self-driving wheelchair is fit with lidar (a detection system which works on the principle of radar but uses laser) and ultrasonic sensors to detect obstacles in its path.
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The sensors and the artificial intelligence embedded programme stop the wheelchair when the obstacle is as close as 20 cm.
If the obstacle is beyond 20 cm, the wheelchair keeps moving until the obstacle comes within the range. In case of a dynamic obstacle – a object placed temporarily at a place and then removed – the artificial intelligence in the programme guides the wheelchair to an alternative path in the mapped area.
Mr. Megalingam also says that the user can choose the speed at which the wheelchair can move – 1.60 km an hour, which is the standard or 1.40 km an hour or a km an hour.
He adds that the team decided to take up the project as an improvement over its earlier model, where the wheelchair moves based on the user's gesture commands. “I developed this wheelchair and was looking at ways to improve it. And, the idea came when I visited California, where I watched the Google's automatic or self-driven car.”
He came back and inducted students Mr. Chinta, Mr. Sreekanth and Mr. Raj, who got selected into the in-house Lab after successfully passing an interview to work as junior researchers. The advantage of working in the Lab is that it is fully funded by the University Management, the assistant professor says.
Mr. Chinta says his two classmates and he worked on Robotic Operating System (ROS) to develop new software, packages and modify existing packages to suit their needs. In the process they learnt the ROS, which is outside their curriculum.
They also learnt several other things in software testing while working on the project, Mr. Sreekanth complements.
The three have since graduated in May 2018 and are about to get placed.
The faculty, Mr. Megalingam says, the team had to develop almost everything from scratch – the wheelchair frame, operating software and programme to control sensors, all of which happened in the University.
After developing the self-driving wheelchair, the team sent it to the Amrita Institute of Medical Sciences' Department of Rehabilitation for use by the people there. “Five doctors, three orthopaedically challenged persons and a nurse used it and found it to be very helpful. In fact, the orthopaedically challenged persons have volunteered to be a part of their future testing process,” he adds.